This invention relates to an intelligent hydropneumatic suspension system of variable attitude for a vehicle, which limits the vehicle pitch and roll in the case of sudden manoeuvres such as strong acceleration or deceleration or taking bends at high speed, and controls vertical forces if separation from the ground takes place.
It is known to control the attitude of a motor vehicle by self-levelling suspension systems able to keep the vehicle in a constant or predetermined spatial attitude as the loads (both static and dynamic) which act on it vary, for example so as to prevent or as far as possible limit any variation in the longitudinal attitude of the vehicle as the weight (due to both luggage and passengers) acting on its rear axle varies, and likewise limit any vehicle pitching or rolling during sudden manoeuvres such as sudden acceleration or deceleration, or the taking of bends at high speed.
The most efficient suspension system is that based on so-called "active hydrualic syspensions" which vary their attitutde in real time as the vehicle attitude varies. Such suspensions are however relatively complicated, require the use of special actuators, are of high energy consumption and in general are of costly construction. As an alternative it is known to use so-called "slow active" pneumatic suspensions which are much simpler and less costly to construct. This latter suspension system has however, the drawback of a relatively long response time, so that even if it is able to ensure self-levelling of the vehicle as the static loads (represented by the luggage and passengers) acting on it vary, it is not totally able to prevent phenomena such as vehicle rolling or pitching during sudden manoeuvres.